There are many types of system monitoring devices which provide a user with the ability to review activities of a system. Providing such ability to a system monitoring device enhances its effectiveness as a diagnostic tool and increases a user's ability to control and maintain the monitored system. There are a number of different types of system monitoring devices which can be utilized to monitor the performance of a system. The device chosen for such monitoring typically depends upon the complexity of the activity being monitored as well as the selected device for displaying the monitored activity to a user. For example, in monitoring the flow of traffic in a computer network, the performance of the network can be monitored by sophisticated software or by an operator trained on a system monitoring device which is monitoring the computer network.
The display of the information in a meaningful fashion is an integral part of a system monitoring device. This is especially true when either the system monitoring device or the system being monitored is a computer based system and also where information leads itself to being displayed in graphical form on the system monitoring device. Data displayed in graphical form can render otherwise meaningless numbers into a form that is comprehensible to a user. In such case, a goal of user interface programming is to display the information in a clear format on a display device, such as a video display terminal. In such a system, if the user desires to either control the information or the process being displayed, the user usually needs to become familiar with the particular computer system that is displaying the information. Therefore, these users might need to become "fluent" in the command structure and language of the particular computer system being used.
To reduce the learning curve in training new users on different system monitoring devices wherein the device is a computer system, a goal is to develop "user-friendly" systems. An example of an advance in user interface programming for computer systems is the use of "windows" to display data on a screen of a video display terminal. A window is an array of pixels which may be partially or wholly visible on the screen of a video display terminal depending upon the size of the window relative to the physical dimensions of the display screen. There are a number of commercially available windowing systems, e.g., DECWindows.RTM. graphics applications from Digital Equipment Corporation, Microsoft.RTM. Windows graphics applications from the Microsoft.RTM. Corporation and Macintosh.RTM. graphics applications from the Apple.RTM. Corporation. Windowing systems provide a user interface to a workstation and perform tasks such as processing user-initiated functions and displaying data on the screen.
Each one of the foregoing windowing systems provides the user with the ability to utilize a pointing device to manipulate information on a display screen of a video display terminal in a workstation. The user is able to manipulate information displayed on the screen by utilizing the pointing device to position a cursor, referred to as the "pointing device cursor," over the displayed information and depress a button on the pointing device. This user action will cause the windowing system to process the request, e.g., by directing the processing to a specific application program dedicated to perform such processing.
There are many occasions where a user utilizing a system monitoring device desires to define a range of values in relation to some set of presented graphical data which relates to a monitored system. Traditional command line user interfaces typically present data in tabular form and allow textual commands to set conditions. Set forth below is an example of the interaction between computer and user in such user interfaces. The user enters a command after the "&gt;&gt;" prompt. The information that follows on the succeeding lines is displayed on the screen of a user's work station in response to the commands entered by the user.
______________________________________ &gt;&gt; SHOW ERRORS/CRC CRC Errors per Hour: 08:00 AM 50 09:00 AM 75 10:00 AM 25 11:00 AM 30 &gt;&gt; SET ALARMON/CRC&gt;85 &gt;&gt; SET ALARMOFF/CRC&lt;55 &gt;&gt; SHOW ALARMON ALARMON=85 &gt;&gt; SHOW ALARMOFF ALARMOFF=55 ______________________________________
Current graphic methods utilizing a windowing environment typically present text boxes for both the high and low values of the user-settable range. The text boxes may or may not be displayed in conjunction with a depiction of the data. Sometimes, along with the ability to select and type values directly into the text boxes, the values within these boxes can also be set using the push buttons of a pointing device to move the values displayed in the text boxes up or down.
Notwithstanding the foregoing advances in user interface programming, it would be highly desirable to have a system monitoring device which allows a user to view either or both historical and real time information, as well as provide a user with the ability to select a range of values to be displayed on the screen of a system monitoring device reflecting system performance in an intuitive manner, without the need for a user to be trained to use the system monitoring device. In particular, it would be highly desirable for such user interface to provide an intuitive relationship with regard to the presented information. In this system, to view information in an intuitive manner, a user who is familiar with a chosen graphical environment would tend to expect that they could directly manipulate and control the information displayed. The more intuitive the process of accessing, displaying, observing historical or real time data and setting values, the less training required, and therefore, the longer the knowledge and/or skills are retained and the easier it is to observe the information being displayed and ascertain its meaning.